Weatherproof electrical heater.



F. KUHN a! 1. A. HAND; WEATEIERPRDOF ElECRICfL HEMER.

A PLICATIUN HLU) JUNE tu; l9l8.

UNITED sTATEs PATENT oEEIoE.

FRANK KUHN AND JAY A. HAND, OF DETROIT, MICHIGAN, ASSIGNOBS T0 AMERICAN ELECTRICAL HEATER COMPANY, UF DETROIT, MICHIGAN, A CORPORATION 0F MICHIGAN.

'WEATHERPROOF ELECTRICAL HEATER.

Specification of Letters Patent.

Patented Dec. 17, 1918.

Application led .Tune 15, 1918. Serial No. 240,148.

To all whom t may concern:

Be it known that we, FRANK KUHN and JAY A. HAND, citizens of the United States of America residing at Detroit, in the county of Wayne and State of Michi an, have invented certain new and useful 1nprovements in lVeatherproof Electrical Heaters, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to portable electric heaters and its object is to provide a portable electric heater employing a substantially water-proof construction that may be exposed to a considerable amount of moisture Without suffering detrimental etl'ect and, consequently, is particularly adapted for use in exposed places as, for example, on the deck of a boat.

In attaining this object the invention contemplates associating' an armored heating element with a termianl box in such a manner that access of water to the electrical connections within said box, is substantially prevented.

In the accompanying drawings:

Figure l is a front view of the heater with portions thereof broken away to show the interiorl construction;

Fig. 2 is an end view of the heater;

Fig. 3 is a vertical transverse sectional view of the same. 4

In these views the reference character l designates a heating element which is wound upon an insulator core as, for example, a sheet'of mica. At each side of said resistor, sheets 3 of mica or other insulating material are disposed and outside of these are arranged metallic connector tively having contact with the extremities of said heating element. Outside of the plates 4 another sheet of insulation 4 is arranged, and the whole is then disposed within a metallic casing or armor 5. The connector plates 4 are respectively formed with lugs 6 projecting below the armor gagement with conductors 6a. The armored heating element thus formed is characterized by a slight thickness as compared with its width. The side plates of the armor 5 are laterally flanged at the bottom thereof, as indicated at 7, and said flanges are secured by suitable means to the upper edges of a metal terminal box 8, forming a closure for the top of said box. Between plates 4 respec- 5 for en'- water-tight and minimizing the passage of heat from the heating element to said terminal box, the material of said gasket being selected to give the desired heat insulating effect. A pair of transverse ribs 10 are formed upon the bottom of the box 8 serving to space the box slightly above an insulatory base 10xl to which the terminal box is rigidly secured b v screws 1()b passing through said base and engaging said ribs. At one end of the terminal box the same is exterior-ly formed with a boss 11 through which is formed anmaxial passage admitting the conductors G to the terminal box. Said boss is counterbored to form a recess receiving a packing ring` 12 surrounding said conductors, said packing being compressed by a gland 13 having threaded engagement with the counterbore.

Said heating element and its terminal box are inclosed within a housing formed by an arched sheet of perforated metal 14 constituting the front, top and back of the housing, the sides of the housing being formed by metal plates 15 of heavier material to which the edges of the sheet 14 are rigidly secured. The members 15 have feet l5a resting upon the base 10El and engaged by screws 16D passing through said base.

. By employing an armored type of heating element and by using packing at the connection between saidl element and the terminal box and at the point of entry of the conductors into said terminal box, access of water or moisture either to the heating re-` sistor or to the electrical connections is very positively prevented. The sides 15 of the housing have handles 16 secured respectively thereto so that the heater may be readily lifted and carried. Besides being weatherproof, the construction is suliiciently strong to withstand considerable hard usage without deterimental effect.

What we claim as our invention, is:

l. A portable electric heater comprising an armored heating unit, a terminal box upon which said unit is rigidly mounted forming a closure for said box, and a conductor entering said terminal box and connected to the unit therewithin. i

2. A portable electric heater comprising an armored heating unit, a terminal box for which said unit forms a closure, packing clamped between said heating unit and terminal box having a heat insulating nature and forming a Weather-proofing joint, and a conductor entering said terminal 'box and having connection with the heating .unit therewithin. Y

3. A portable electric heater comprising an armored heating unit, a terminal box upon which said unit is mounted and for which it forms a closure, a conductor entering said terminal box through an aperture therein, and means preventing the passage of moisture through said aperture.

4. A portable electric heater com rising an armored heating unit, a terminal ox on which Said unit is mounted and for which it forms a closure, said box being formed with an exterior boss having an axial passage therethrough, a conductor entering the terminal box through said passage and connected to the heating unit therein, a packing ring Surrounding said conductor Within a recess of said boss, and a packing gland en gaging said boss and apertured to give passage to said conductor.

5. A portable electric heater comprising an armored heating unit, a terminal box upon which said unit is mounted, a base to which said terminal box is secured, and a housing secured to said base and inclosing said heating unit and terminal box.

6. A portable electric heater comprising an armoredA heating unit a terminal box upon which said unit is mounted so as to form a closure for said box, a conductor entering said terminal box and connected to the unit therewithin, and a perforated housing spaced from and inclosing said heating unit.

In testimony whereof we aliix our signatures. r V

FRANK KUHN. JAY A. HAND. 

